PHILADELPHIA (CBS) — The suspect, who was arrested after allegedly attempting to carry explosives on a plane at Philadelphia International Airport, was released on house arrest Tuesday.

Joseph Picklo, 29, of Dallas, Pa., was released on house arrest and must wear ankle bracelet while staying with his parents in the Bridesburg section of the city. Authorities said Picklo also tested positive for drugs and will have to undergo repeat drug testing as a result.

Picklo was arrested on March 29 after an explosive substance was found in his luggage while being screened for a United Airlines flight to San Francisco. Picklo was immediately taken into custody by Philadelphia police and then transferred to federal custody.

The incident remains under investigation by the Philadelphia Police Department, the U.S. Department of Transportation, the Bureau of Alcohol, Tobacco, Firearms, and Explosives, the Transportation Security Administration, and the FBI.